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2012 GMC Sierra warm up issue

I have a 2012 Sierra 1500 SLE with a 5.3 liter engine, 6 speed transmission and about 7700 miles. I have noticed that at times the truck does not seem to be performing efficiently and will not seem as smooth and transmission shifting is sometimes not so smooth in the lower gears. I have noticed that when I let the truck warm up for about a minute before putting it in gear, that all seems to go much more smoothly, but if I crank up cold and take off right away, then it tends to run not as smooth. I have even heard a slight “slap” type noise that I think is the transmission shifting when slowing down to make a turn at about 15-20 MPH. When I go to accelerate after the turn, it will sometimes slap as if it is hunting for the right gear. Obviously, I now let it warm up for a minute before I drive it, but I am wondering if anyone else has had this type of issue and if it is something that I should worry about? I have not talked to the dealer, but I probably will when I take it in for its 10K checkup. Any advice?

How cold is it where you live? If you live in Miami…you may have a slight problem. If you live in Alaska then let the vehicle warm up a couple of minutes before you take off.